Demonstration of universal parametric entangling gates on a multi-qubit lattice.

We show that parametric coupling techniques can be used to generate selective entangling interactions for multi-qubit processors. By inducing coherent population exchange between adjacent qubits under frequency modulation, we implement a universal gate set for a linear array of four superconducting qubits. An average process fidelity of ℱ = 93% is estimated for three two-qubit gates via quantum process tomography. We establish the suitability of these techniques for computation by preparing a four-qubit maximally entangled state and comparing the estimated state fidelity with the expected performance of the individual entangling gates. In addition, we prepare an eight-qubit register in all possible bitstring permutations and monitor the fidelity of a two-qubit gate across one pair of these qubits. Across all these permutations, an average fidelity of ℱ = 91.6 ± 2.6% is observed. These results thus offer a path to a scalable architecture with high selectivity and low cross-talk.

¿Dónde Estamos? La Cultura Laboral Chilena desde Hofstede / Where Are We? Chilean Labor Culture since Hofstede / Onde Estamos? A Cultura Organizacional Chilena a partir de Hofstede

Resumen 36 años después de la primera publicación del estudio de culturas nacionales desarrollado por Hofstede, se emprende un nuevo ejercicio para evaluar la configuración de valores de Chile. Este trabajo se enfocó en el diagnóstico de la capacidad de replicar los resultados obtenidos en estudios anteriores, a través de una muestra representativa de la población eco nómicamente activa, y buscó integrar otros estudios sobre la llamada cultura organizacional chilena. En este sentido, se llevan a cabo consideraciones respecto a la calidad de los datos y los vacíos metodológicos que presentan las mediciones anteriores y se propone cuál sería la actual configuración de la cultura laboral chilena.

Summary 36 years after Hofstedes first study of national cultures, we did a new exercise to evaluate Chile's value configuration. This work focused on the ability to replicate the results obtained in prior studies using a representative sample of the economically active population, integrating other studies on the Chilean organizational structure. The study considers the data quality and the methodological gaps of the prior measurements and proposes the Chilean work culture's cur rent configuration.

Resumo 36 depois da primeira publicação do estudo de culturas nacionais desenvolvido por Hofstede, empreende-se um novo exercício para avaliar a configuração de valores do Chile. Este trabalho focou no diagnóstico da capacidade de reprodu zir os resultados obtidos em estudos anteriores por meio de uma amostra representativa da população economicamente ativa e pretendeu integrar outros estudos sobre a chamada cultura organizacional chilena. Nesse sentido, realizam-se considerações a respeito da qualidade dos dados e dos vazios metodológicos que as medições anteriores apresentam e propõe-se qual seria a atual configuração da cultura organizacional chilena.

To know you is to love you: Effects of intergroup contact and knowledge on intergroup anxiety and prejudice among indigenous Chileans.

Two surveys were conducted in Chile with indigenous Mapuche participants (N study 1: 573; N study 2: 198). In line with previous theorising, it was predicted that intergroup contact with the non-indigenous majority reduces prejudice. It was expected that this effect would be because of contact leading to more knowledge about the outgroup, which would then lead to less intergroup anxiety. The two studies yielded converging support for these predictions.

Beyond the 'east-west' dichotomy: Global variation in cultural models of selfhood.

Markus and Kitayama's (1991) theory of independent and interdependent self-construals had a major influence on social, personality, and developmental psychology by highlighting the role of culture in psychological processes. However, research has relied excessively on contrasts between North American and East Asian samples, and commonly used self-report measures of independence and interdependence frequently fail to show predicted cultural differences. We revisited the conceptualization and measurement of independent and interdependent self-construals in 2 large-scale multinational surveys, using improved methods for cross-cultural research. We developed (Study 1: N = 2924 students in 16 nations) and validated across cultures (Study 2: N = 7279 adults from 55 cultural groups in 33 nations) a new 7-dimensional model of self-reported ways of being independent or interdependent. Patterns of global variation support some of Markus and Kitayama's predictions, but a simple contrast between independence and interdependence does not adequately capture the diverse models of selfhood that prevail in different world regions. Cultural groups emphasize different ways of being both independent and interdependent, depending on individualism-collectivism, national socioeconomic development, and religious heritage. Our 7-dimensional model will allow future researchers to test more accurately the implications of cultural models of selfhood for psychological processes in diverse ecocultural contexts. (PsycINFO Database Record

Individual and culture-level components of survey response styles: A multi-level analysis using cultural models of selfhood.

Variations in acquiescence and extremity pose substantial threats to the validity of cross-cultural research that relies on survey methods. Individual and cultural correlates of response styles when using 2 contrasting types of response mode were investigated, drawing on data from 55 cultural groups across 33 nations. Using 7 dimensions of self-other relatedness that have often been confounded within the broader distinction between independence and interdependence, our analysis yields more specific understandings of both individual- and culture-level variations in response style. When using a Likert-scale response format, acquiescence is strongest among individuals seeing themselves as similar to others, and where cultural models of selfhood favour harmony, similarity with others and receptiveness to influence. However, when using Schwartz's (2007) portrait-comparison response procedure, acquiescence is strongest among individuals seeing themselves as self-reliant but also connected to others, and where cultural models of selfhood favour self-reliance and self-consistency. Extreme responding varies less between the two types of response modes, and is most prevalent among individuals seeing themselves as self-reliant, and in cultures favouring self-reliance. As both types of response mode elicit distinctive styles of response, it remains important to estimate and control for style effects to ensure valid comparisons.

Enhanced nonlinear interactions in quantum optomechanics via mechanical amplification.

The quantum nonlinear regime of optomechanics is reached when nonlinear effects of the radiation pressure interaction are observed at the single-photon level. This requires couplings larger than the mechanical frequency and cavity-damping rate, and is difficult to achieve experimentally. Here we show how to exponentially enhance the single-photon optomechanical coupling strength using only additional linear resources. Our method is based on using a large-amplitude, strongly detuned mechanical parametric drive to amplify mechanical zero-point fluctuations and hence enhance the radiation pressure interaction. It has the further benefit of allowing time-dependent control, enabling pulsed schemes. For a two-cavity optomechanical set-up, we show that our scheme generates photon blockade for experimentally accessible parameters, and even makes the production of photonic states with negative Wigner functions possible. We discuss how our method is an example of a more general strategy for enhancing boson-mediated two-particle interactions and nonlinearities.

Fast Quantum Nondemolition Readout by Parametric Modulation of Longitudinal Qubit-Oscillator Interaction.

We show how to realize fast and high-fidelity quantum nondemolition qubit readout using longitudinal qubit-oscillator interaction. This is accomplished by modulating the longitudinal coupling at the cavity frequency. The qubit-oscillator interaction then acts as a qubit-state dependent drive on the cavity, a situation that is fundamentally different from the standard dispersive case. Single-mode squeezing can be exploited to exponentially increase the signal-to-noise ratio of this readout protocol. We present an implementation of this longitudinal parametric readout in circuit quantum electrodynamics and a possible multiqubit architecture.

Heisenberg-Limited Qubit Read-Out with Two-Mode Squeezed Light.

We show how to use two-mode squeezed light to exponentially enhance cavity-based dispersive qubit measurement. Our scheme enables true Heisenberg-limited scaling of the measurement, and crucially, it is not restricted to small dispersive couplings or unrealistically long measurement times. It involves coupling a qubit dispersively to two cavities and making use of a symmetry in the dynamics of joint cavity quadratures (a so-called quantum-mechanics-free subsystem). We discuss the basic scaling of the scheme and its robustness against imperfections, as well as a realistic implementation in circuit quantum electrodynamics.

Nonlinear interaction effects in a strongly driven optomechanical cavity.

We consider how nonlinear interaction effects can manifest themselves and even be enhanced in a strongly driven optomechanical system. Using a Keldysh Green's function approach, we calculate modifications to the cavity density of states due to both linear and nonlinear optomechanical interactions, showing that strong modifications can arise even for a weak nonlinear interaction. We show how this quantity can be directly probed in an optomechanically induced transparency-type experiment. We also show how the enhanced interaction can lead to nonclassical behavior, as evidenced by the behavior of g(2) correlation functions.